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131.
Palwinder Singh Jatinder Kaur Bhawna Yadav Sneha Sudha Komath 《Bioorganic & medicinal chemistry》2009,17(11):3973-3979
In order to search for MDR modulators, rationally designed acridone derivatives were investigated for their effect on influx or efflux of Rhodamine6G (R6G) in CAI4 cells. Results of these investigations indicate that in presence of compound 12, inhibition of growth of CAI4 cells and also an increased influx/efflux of R6G in CAI4 cells have been observed. This seems to be occurring due to the cell wall rupturing of Candida albicans. Compound 12 may be a suitable candidate for candidiasis therapy. 相似文献
132.
The reinforcement of natural biopolymers with cellulosic whiskers has been shown to be beneficial for physical strength properties including xylan films. This study examines the water transmission properties of xylan films reinforced with cellulosic whiskers prepared from kraft pulp hydrolyzed with sulfuric acid. Measurements of water transmission rate (WVTR) were accomplished by a modification of wet cup method described by ASTM E 96-95. The results showed that films prepared by xylan reinforced by 10% sulfonated whiskers exhibited a 74% reduction in specific water transmission properties with respect to xylan film and a 362% improvement with respect to xylan films reinforced with 10% softwood kraft fibers. 相似文献
133.
Rohit Saxena Praveen Vashist Radhika Tandon R. M. Pandey Amit Bhardawaj Vimala Menon Kalaivani Mani 《PloS one》2015,10(2)
PurposeAssess prevalence of myopia and identify associated risk factors in urban school children.MethodsThis was a cross-sectional study screening children for sub-normal vision and refractive errors in Delhi. Vision was tested by trained health workers using ETDRS charts. Risk factor questionnaire was filled for children with vision <6/9.5, wearing spectacles and for a subset (10%) of randomly selected children with normal vision. All children with vision <6/9.5 underwent cycloplegic refraction. The prevalence of myopia <-0.5 diopters was assessed. Association of risk factors and prevalence of myopia was analyzed for children with myopia and randomly selected non myopic children and adjusted odds ratio values for all risk factors were estimated.ResultsA total number of 9884 children were screened with mean age of 11.6 + 2.2 years and 66.8% boys. Prevalence of myopia was 13.1% with only 320 children (24.7%) wearing appropriate spectacles. Mean myopic spherical error was -1.86 + 1.4 diopters. Prevalence of myopia was higher in private schools compared to government schools (p<0.001), in girls vs. boys (p = 0.004) and among older (> 11 years) children (p<0.001). There was a positive association of myopia with studying in private schools vs. government schools (p<0.001), positive family history (p< 0.001) and higher socio-economic status (p = 0.037). Positive association of presence of myopia was observed with children studying/reading > 5 hours per day (p < 0.001), watching television > 2 hours / day (p < 0.001) and with playing computer/video/mobile games (p < 0.001). An inverse association with outdoor activities/playing was observed with children playing > 2 hours in a day.ConclusionMyopia is a major health problem in Indian school children. It is important to identify modifiable risk factors associated with its development and try to develop cost effective intervention strategies. 相似文献
134.
Deeksha Pandey Parnita Sardana Aashish Saxena Luvdeep Dogra Ambika Coondoo Asha Kamath 《PloS one》2015,10(5)
IntroductionPresent study was aimed to analyze the impact of education, employment and financial independence in breastfeeding practices among Indian women.MethodologyPresent explorative questionnaire based survey included 256 women (128 pairs) in the final analysis. A pair means – a) pregnant lady (in her third trimester) representing younger generation and b) her mother/mother in law representing the elder generation.ResultsWe found that the overall awareness regarding ‘breast milk’ being the best food for baby was excellent (overall 97.3%; younger generation: 96.9%; elder generation: 97.7%). Overall knowledge regarding the correct technique (28.9% younger generation and 21.9% elder generation) and frequency of breastfeeding (20.3% of younger generation and 34.4% of elder generation) was very poor. Less than 60% (younger generation: 57.8%; elder generation: 58.6%) were aware that the only major contraindication for breastfeeding is a mother infected with human immunodeficiency virus (HIV). On comparing responses obtained from the two generations of women, difference was not statistically significant among most of the issues related to breastfeeding. With regards to the attitude, despite better awareness, only 94.5% women in younger generation and 89.1% women in elder generation were planning to give mother’s milk as the first feed to the newborn. Similarly, less than 75% of women were ready to breast-feed the newborn immediately after birth. This was contradictory to the fact that 86% of pregnant women were aware that the baby should be breast-fed within an hour of birth.ConclusionAwareness with regards to breastfeeding issues had not changed significantly with the educational progress of Indian women. Despite the good level of awareness in the society regarding breastfeeding, attitude to practice the same is lacking. 相似文献
135.
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137.
Reshu Saxena Sudipti Gupta Kavita Singh Kalyan Mitra Anil Kumar Tripathi Raj Kamal Tripathi 《PloS one》2015,10(4)
Nef is an accessory viral protein that promotes HIV-1 replication, facilitating alterations in cellular pathways via multiple protein-protein interactions. The advent of proteomics has expanded the focus on better identification of novel molecular pathways regulating disease progression. In this study, nef was sequenced from randomly selected patients, however, sequence variability identified did not elicited any specific mutation that could have segregated HIV-1 patients in different stages of disease progression. To explore the difference in Nef functionality based on sequence variability we used proteomics approach. Proteomic profiling was done to compare the effect of Nef variants in host cell protein expression. 2DGE in control and Nef transfected SupT1 cells demonstrated several differentially expressed proteins. Fourteen protein spots were detected with more than 1.5 fold difference. Significant down regulation was seen in six unique protein spots in the Nef treated cells. Proteins were identified as Cyclophilin A, EIF5A-1 isoform B, Rho GDI 1 isoform a, VDAC1, OTUB1 and α-enolase isoform 1 (ENO1) through LC-MS/MS. The differential expression of the 6 proteins was analyzed by Real time PCR, Western blotting and Immunofluorescence studies with two Nef variants (RP14 and RP01) in SupT1 cells. There was contrasting difference between the effect of these Nef variants upon the expression of these six proteins. Downregulation of α-enolase (ENO1), VDAC1 and OTUB1 was more significant by Nef RP01 whereas Cyclophilin A and RhoGDI were found to be more downregulated by Nef RP14. This difference in Nef variants upon host protein expression was also studied through a site directed mutant of Nef RP01 (55AAAAAAA61) and the effect was found to be reversed. Deciphering the role of these proteins mediated by Nef variants will open a new avenue of research in understanding Nef mediated pathogenesis. Overall study determines modulation of cellular protein expression in T cells by HIV-1 Nef variants. 相似文献
138.
Ozlen Saglam Erik Samayoa Sneha Somasekar Samia Naccache Akiko Iwasaki Charles Y Chiu 《PloS one》2015,10(4)
Vulvar Intraepithelial Neoplasia (VIN) is the precursor lesion of Vulvar Squamous Cell Carcinoma (VSCC), and the differentiated type (dVIN) is more frequently observed in relation to VSCC. In contrast to usual-type VIN (uVIN), which is related to infection by human papillomavirus (HPV), a germline mutation in the p53 gene is thought to be associated with ~90% of dVIN cases. To date, no infectious agent has been identified in association with dVIN, and studies investigating this possibility have been hindered by the difficulty in accurately diagnosing dVIN from small biopsies. Here, we used immunostaining for p16ink4a, a biomarker for HPV infection, to study 14 uVIN high-grade VIN and 14 dVIN cases, and to select 10 dVIN cases to broadly screen for all known viruses using a pan-viral microarray platform (ViroChip). All of the uVIN tissue samples, including 8 warty and 6 basaloid cases, showed positivity with the p16ink4a immunostain. The staining pattern was full-thickness for all except two cases in which positive staining was localized in the lower 1/3 of the epidermis. In contrast, immunostaining for p16ink4a was negative in all dVIN cases. ViroChip analysis of 10 pure dVIN samples confirmed the absence of human papillomavirus subtypes or any other virus with the exception of a single sample that showed a weak microarray signature to a porcine herpesvirus. Follow-up PCR testing of the sample was negative for herpesvirus, and in-depth metagenomic next-generation sequencing revealed only sequences corresponding to non-pathogenic viral flora and bacterial contamination. In this study, we demonstrated lack of a virus association in 10 dVIN cases. Alternative pathways for carcinogenesis such as the p53 mutation should be considered for investigation of potential treatment options in dVIN. 相似文献
139.
Radha Vaddavalli Sneha Peddi Srilekha Yadav Kothagauni Venkateswar Rao Linga 《Antonie van Leeuwenhoek》2014,105(3):443-450
A novel actinomycete strain, designated VRC07T, was isolated from a Callistemon citrinus rhizosphere sample collected from Hyderabad, India. Its taxonomic status was determined by using polyphasic approach. It is a Gram-positive, aerobic, non-motile, weakly acid-fast strain. Phylogenetic analysis based on the 16S rRNA gene sequence revealed that strain VRC07T is a member of the genus Nocardia. The highest levels of 16S rRNA gene sequence similarity was found between the strains Nocardia niwae W9241T (99.6 %), Nocardia amikacinitolerans W9988T (99.3 %) and Nocardia arthritidis IFM 10035T (98.9 %); similarity to other type strains of the genus Nocardia was below 98.7 %. The organism had chemical and morphological features consistent with its classification in the genus Nocardia such as meso-diaminopimelic acid as the diagnostic diamino acid in the cell wall peptidoglycan. Arabinose and galactose as the diagnostic sugars. Diagnostic polar lipids were phosphatidylinositol, diphosphatidylglycerol, and phosphatidylglycerol. The predominant menaquinone was MK-8(H4, ω-cycl). The major fatty acids were C16:0, C18:0, C18:1 w9c, C18:0 10-methyl TBSA and sum in feature 3 (16:1 w7c/16:1 w6c). The G+C content of the genomic DNA was 68.5 mol%. The DNA–DNA relatedness data, together with phenotypic differences clearly distinguished the isolate from its closest relatives. On the basis of these phenotypic and genotypic data, the isolate represents a novel species, for which the name Nocardia bhagyanesis sp. nov., is proposed. The type strain is VRC07T (=KCTC 29209T = MTCC 11725T = ATCC BAA-2548). 相似文献
140.
Mesenchymal stromal cells (MSCs) show promise in cell-based transplantations and regenerative medicine applications. MSCs from Wharton’s jelly (WJ) of umbilical cord can be easily harvested and exhibit greater proliferative activity than bone marrow MSCs. It is important to develop a practical cryopreservation technique to effectively store umbilical cord for potential future applications. Successful cryopreservation would allow access to umbilical cord from the same donor for repeated WJ MSC-based transplantations. For therapeutic applications, one should be able to obtain clinically-relevant quality and quantity of MSCs from cryopreserved tissues. In this study, we optimised a serum-free formulation of 10% dimethyl sulfoxide (DMSO) and 0.2 M sucrose for cryopreservation of umbilical cord tissue. Slow freezing and rapid thawing were adopted. MSCs harvested from WJ of cryopreserved umbilical cord could undergo robust expansion, differentiate to mesodermal lineages and express MSC-characteristic surface antigens. The cumulative cell yield, however, was less compared to corresponding fresh cord tissue. 相似文献